noun ad·di·tion \ə-ˈdi-shən, a-\

: the act or process of joining something to something else : the act or process of adding something

mathematics : the act or process of adding numbers

: something or someone more that is included : something or someone that is added

Full Definition of ADDITION

:  a part added (as to a building or residential section)
:  the result of adding :  increase
:  the act or process of adding; especially :  the operation of combining numbers so as to obtain an equivalent simple quantity
:  direct chemical combination of substances into a single product
in addition
:  2besides, also
in addition to
:  combined or associated with :  1besides 2

Examples of ADDITION

  1. The children learned addition and subtraction.
  2. The museum's collection includes several new additions.

Origin of ADDITION

addicion Anglo-French, from Latin addition-, additio, from addere
First Known Use: 14th century

Other Building Terms

batten, cistern, hearth, lath, transom, wainscot
ADDITION Defined for Kids


noun ad·di·tion \ə-ˈdi-shən\

Definition of ADDITION for Kids

:  the act or process of adding numbers to obtain their sum
:  something added <an addition to a house>
in addition
:  as something more
in addition to
:  along with or together with <There was ice cream in addition to cake and pie.>
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